A reliable characterization method giving a detailed hydrocarbon compositio
n profile for transportation fuels is an important part of any process that
optimizes fuel reformulation and engine design to reduce regulated emissio
ns. This study describes the development of a modified gas chromatography f
ield ionization mass spectrometry (GC-FIMS) method for detailed hydrocarbon
type determination of diesel fuel. Diesel fuels were analyzed by GC-FIMS,
and the calculated hydrocarbon type composition profile was compared with t
hat determined by other standard techniques. Results for total saturates, t
otal aromatics, monoaromatics, and polyaromatics contents correlated well.
Selected ion chromatograms demonstrated the separation of isoparaffins and
normal paraffins in typical diesel fuels. The GC-FIMS method produced resul
ts for isoparaffin, normal paraffin, and cycloparaffin contents that did no
t require sample pretreatment to separate saturates and aromatics fractions
. Analysis of a gasoline sample showed excellent agreement between GC-FIMS
and detailed hydrocarbon analysis or PIONA for total cycloparaffin content,
and reasonable agreement for iso- and normal paraffin contents. The normal
paraffin contents of selected diesel blends measured by GC-FIMS correlated
well with that measured by other methods. Experiments with internal standa
rdization verified the accuracy of the GC-FIMS method for selected hydrocar
bon isomers.